5.56 Short Barrel loads

[Danimal]

Anyone have any good SBR loads for 5.56? Looking to maximize velocity while dialing back the fireball out of a 10.5". I have a bunch of 62 gn projectiles, and I am thinking that using the heavier bullet will be a little better allowing for a little slower acceleration and achieving higher energy than a 55gn round. I have been digging around online, and the threads are all over the map. Also the cleaner the better, I am running a suppressor so I am trying to clean that up a bit too.

Really I am planning on tinkering with this for a while, so any testing or experience that you have with load development whether it worked or not would be appreciated.

[Danimal]

Man It has really quieted down around these parts. I guess there is not much reloading happening when you cant get reloading supplies...

I have been doing a little math and I think that I have the solution. I am going to try CFE BLK and see if I can get the gun to cycle and see where velocities end up. It is a little faster burning than I wanted to go, but if I walk it up slowly it should be just fine. There are loads out there for 221 fireball with CFE BLK that seem to work well, and in this case it will be a pretty similar application with the burn rate optimized for a 9" barrel. These loads were reported to max PSI of 49k at 21.x gn so there is still some room in the 5.56 platform.

I am going to make some test loads up with CFE BLK and Reloader 10x and will compare the performance to factory M855 and M193.

[zimagold]

I like H335 for 55s. I would not say optimal, but it was the best of a half dozen when considering cleanliness, velocity, and fireball for my shorter barrels, 11.5-14.5.

[ChadAmberg]

I've heard that you want faster burning powders in SBRs. Where's that burn rate chart...

IMR-4198, RL-10x, N-133, IMR-3031, TAC are all much faster than Varget for example. So your 10x should be better performing than most other options!

[Great-Kazoo]

Man It has really quieted down around these parts. I guess there is not much reloading happening when you cant get reloading supplies...

I have been doing a little math and I think that I have the solution. I am going to try CFE BLK and see if I can get the gun to cycle and see where velocities end up. It is a little faster burning than I wanted to go, but if I walk it up slowly it should be just fine. There are loads out there for 221 fireball with CFE BLK that seem to work well, and in this case it will be a pretty similar application with the burn rate optimized for a 9" barrel. These loads were reported to max PSI of 49k at 21.x gn so there is still some room in the 5.56 platform.

I am going to make some test loads up with CFE BLK and Reloader 10x and will compare the performance to factory M855 and M193.



A2230, TAC, or xterminator, is what i run out of a 12" 1:8 bbl. 335 is ok as a fall back, CFE Black, eh i'd pass. Take a look at the SW (Shooters World) powders. Also if you chrono your standard load for carbine, using one of the powders i mentioned. You should see minimal FPS variation

The varget is not a 1st pick, for me, to load for a sbr.

[Tim K]

TAC under 77sMKs gets me 2500+ FPS out of my 11.5”.

[Danimal]

I would like to try TAC in the future when I can get ahold of some. My problem with the 77s was they had to be seated so deep that the ogive started to gap at the case mouth. Otherwise they would not fit in my mags. It was not a ton, but enough. What is your OAL and do you have the same problem? I also tried the heavy Hornady match stuff and had the same problem. I could probably get them to run great in a bolt gun, but in an AR with P-mags I was having a lot of trouble.

Just got back from testing the 10X and CFE-BLK. I have to be honest I really liked both and the CFE-BLK was really nice, no fireball, really quiet suppressed, very low recoil, and honestly really clean on the brass and back in the chamber out of my 10.5". I used 222 rem data and loaded 55gn projectiles and was really conservative on the loads and have a lot of room at the top. 18 gns got me 2400fps with no real fireball and I can tell it is still super low pressure overall. I am confident that I can get the 2700 fps or so I was getting with M193. My main goal is to get something I can reload for pretty cheap that has good performance and runs cooler through my suppressor, and so far both options seem to work well.

[Danimal]

Here is some of the data from today. I am still just really happy that both the RL10x and the CFE-BLK were so much cleaner. The M193 was brand new manufactured this year and as bright as can be before firing, and like so much other factory stuff was just crazy dirty when using a suppressor. I use a 30 cal suppressor, so the back pressure is really not even that high.

Looking closer at the CFE-BLK I am starting to see a little bit of flattening and flow of the primer at 18 gn so I will walk up really slowly and see if I can get up to the performance of the 193 then compare them in terms of fireball noise and accuracy.

87244

87245

87246

[ChadAmberg]

I would like to try TAC in the future when I can get ahold of some. My problem with the 77s was they had to be seated so deep that the ogive started to gap at the case mouth. Otherwise they would not fit in my mags. It was not a ton, but enough. What is your OAL and do you have the same problem? I also tried the heavy Hornady match stuff and had the same problem. I could probably get them to run great in a bolt gun, but in an AR with P-mags I was having a lot of trouble.



I saw TAC available on the Hodgon website for sale yesterday I think... yup still in stock https://shop.hodgdon.com/ramshot/ramshot-tac

[Danimal]

I saw TAC available on the Hodgon website for sale yesterday I think... yup still in stock https://shop.hodgdon.com/ramshot/ramshot-tac

Dang, I keep forgetting they started selling direct to consumer. I will have to pick some up.

[sportbikeco]

5.56 is always going to suffer with that short of a barrel. 30 cal supressor already? 7.62x39 doesn't give up much in a 10" config.

[Tim K]

I load them right out to magazine length. No problems. Not sure what the coal is because I measure to the ogive, but it?s close to the max of 2.260?. I?m surprised you?re having problems.